电站锅炉管阵列内声传播特性及时延值测量

Acoustic Propagation and TDOA Measurement in Tube Arrays of Utility Boiler

对电站锅炉管阵列内声传播特性及时延值进行研究,利用Fluent软件对非均匀温度场与均匀温度场、不同管排数及不同布置方式的管阵列内声传播特性进行对比,并搭建管阵列实验台,引入快速集合经验模态分解(EEMD)算法对管阵列内时延值进行测量.结果表明:管阵列内声传播存在声阻带,且在非均匀温度场集合经验模态分解下声阻带向低频段移动,管排数越多,声阻带效应越明显,管道间节距对错列与顺列布置方式下的声阻带有一定影响;基于快速EEMD处理,选用低频段声信号能够获得有效时延值.

A study was conducted on acoustic propagation and TDOA measurement in tube arrays of utility boiler, where the propagation characteristics were numerically compared using Fluent software under the conditions of uniform/non-uniform temperature field, and different rows of tubes in different arrangements, while the TDOA in tube arrays was measured on a self-developed test bench by Fast EEMD algorithm. Results show that acoustic band gaps exist in the tube array, which move to low frequency area in non-uniform temperature field. With the rise of tube rows, the effect of acoustic band gap becomes more obvious. Tube pitch has a certain influence on the band rejection in both sequence and stagger arrangement of tubes. Based on Fast EEMD algorithm, effective TDOA can be obtained when low frequency signals are chosen.